1. Field of the Invention
This invention relates generally to electrical energy storage and more specifically, to storing the energy discharged from a capacitive load.
2. Description of the Related Art
Harvesting energy from intermittent mechanical disturbances can be of great value for powering remote sensors as well as a wide array of other types of devices. Even if the disturbances are relatively insignificant at any given frequency and do not produce a substantial amount of energy, the total energy collected over a wide frequency spectrum might still be enough to supply power if a suitable means of transduction is available. Piezoelectric transducers are made of materials which possess the property of being able to transform mechanical forces into an output electrical energy. In a piezoelectric device, positive and negative electrical charges are separated when the material from which the device is made undergoes strain and a voltage is generated across the material.
In general, the amplitude of the generated electrical signal is a function of the size of the piezoelectric device and the level of strain or stress applied to it. The frequency of the generated electrical signal is a function of the frequency of the stress and strain to which the piezoelectric device is subjected. When an oscillatory strain such as a vibration is applied to a piezoelectric material, the amplitude and frequency of the generated signal may vary considerably depending on the material itself and the ability of the device to couple mechanical vibrations into stain within the piezoelectric device.
While various apparatus and methodologies have been developed for accumulating generated energy, no design has emerged that generally encompasses all of the desired characteristics as hereafter presented in accordance with the subject technology.